Summary

The budding yeast Saccharomyces cerevisiae has been instrumental in discovering molecular mechanisms of fundamental cellular processes in eukaryotes, including cell cycle control, transcription, chromatin structure, and signal transduction. Missing from this picture has been RNA interference (RNAi), a major regulatory pathway in eukaryotic cells that silences gene expression through small interfering RNAs (siRNAs) that bind target sequences (1–3). On page 544 of this issue, Drinnenberg et al. (4) show that RNAi is indeed present in some budding yeasts and can be restored in S. cerevisiae, opening exciting possibilities for studies focused on the biological functions and impact of RNAi in these organisms.